BATTLEZONE
2 versions exist, with the only difference being with the E1 ROM. The 1st version (rev 1) displays one tank icon for every 100K points, up to 10 of them - only about 5 actually fit on-screen; more than that will be drawn off-screen, causing the display to glitch when scores reach 1 million. The 2nd version (rev 2) only displays a single icon for any score over 100K points. This is the only difference between the 2 versions.
2 different early names were used Future Tank and Moon Tank. From programmer, Ed Rotberg: "I believe the working title was Future Tank. There couldn't have been more than 2 or 3 made under that name. By the time we got to AMOA (Amusement and Music Operators Association - the main trade show) it had been given its final name. At one time it looked like it was going to be called Moon Tank, so when I was told to put some vectors together for a planet, I looked in my Almanac and did a crude picture of the East coast of Australia.". Also, a prototype of a cocktail version was developed, including full glass-top artwork and control panel. Only one is known to exist as it was not released for production.
A special version was designed for the U.S. Army, commonly referred to as Army Battlezone. Only 2 were made. The first version is called the IFV (Infantry Fighting Vehicle) and was sent to Ft. Eustice, VA. It used a down-sized controller that was adapted from an actual Bradley. The second version is called the Bradley Trainer (or the Bradley Fighting Vehicle), and the controller was slightly redesigned, which was later used in Star Wars and a few other games (pictures #1-#6). The game is more a simulation, solely designed for the purpose of training tank gunners. The other tanks do not fire at you (although their turrets will *flash* to show they are), and the only way to end the game is to run out of ammo or shoot a 'friendly' tank or helicopter. A small blurb about the game appeared in the first issue of Atari Age (picture #7).
Missiles will jump over any objects in your path, but if you hide behind an object while a missile attacks, it will jump over both the object and your tank!
After launching the 6th missile, the game replaces slow tanks with super tanks. After another 123 missiles, the game reverts to slow tanks. This happens because the game initializes an 8-bit counter to $ff and increments it on every missile launch, creating super tanks when the count is between 5 and 127 inclusive.
The initials of the some of the programming team are on the high score table at power-up
(picture #9):
EDR Ed Rotberg (programmer)
MPH Morgan P. Hoff
JED Jed Margolin (engineer)
DES Doug Snyder
TKE ?
VKB ?
EL Ed Logg?
HAD Howard Delman
ORR Owen Rubin (programmed volcano activity)
GJR Greg Rivera?
Some revisions of the AUX board have a pot to adjust the pitch of the tank sound. The pot, a 250k Ohm trimmer pot, is at R11, attached to the 555 at F3. The boards that are not adjustable use a 120k Ohm resistor at R11 in place of the trimmer. The trimmer is shown on the 1st printing schematics (picture #10) and the AUX boards all seem to have the pads so it could be that the later revisions were cost cutting. However, one board was found with a lower serial number of *06234 and a Dec 20 1980 test date which has the 120k Ohm resistor. Another board was found with serial number 30028 and no test date which has the 250k Ohm trimmer pot.
BUG: There have been several examples of a glitch that will award the player a score in the millions. One person stated they shot at a saucer, and while the shot was in the air, a missile approached, and hit the missile immediately after the saucer was hit, and ended up with a score over 4 million. Heres a page with photos of several others: https://forums.arcade-museum.com/media/albums/bz-score-bug-glitch-pics.841/ Someone else mentioned getting 300,000 points for hitting a missile, so the missile possibly seems to be involved with this glitch. From Ed Rotberg: The scoring glitch was an extremely rare bug that we were never able to recreate in our testing. We knew it was real, but all our efforts to find it or recreate it failed. It did not come up during development, but shortly after the game had been shipping to the market. We never saw it during development, or testing as far as I can recall. Given the manufacture/sales cycle of arcade games at that time it quickly became somewhat moot, given the rarity of occurrences.
BUG: If the game is left on a long time or played for a long time, it may put up a bizarre score in hex. {Ed Rotberg}
BUG: The enemy spawn code does not check for collisions, so enemy tanks can spawn inside obstacles. The code for moving enemy tanks in reverse also doesn't check for collisions, allowing them to back out.
BUG: With the RAM test, if there's a fault in low RAM ($0000-03ff), the self-test code will mis-report the problem. The bug could be fixed by moving the TXA at $7c89 to come before the preceding BCC, so that the code at $7c8c would have the failing page number in X-reg. {Phil Lapsley}
BUG: The Spanish translation of the enemy position text uses the adjective "muy", so instead of "enemy to right" (English / French / German) it says "enemy far to the right".
RUMOR: A rare glitch occurs when you shoot a saucer and then immediately hit a missile (or something else?). The sound effects for both will conflict with each other and then youll receive a really high score (at least 1 million).
RUMOR: Backing into a saucer is worth twice as many points (10,000).
